Create extensions directory.

[plcapi.git] / extensions / README.txt

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+Create a database extension by creating a tree like follows:
+
+- /usr/share/plc_api/extensions/<name>-up*
+Contains the SQL or script that sets up the extension's database needs.
+
+- /usr/share/plc_api/extensions/<name>-down*
+Contains the SQL or script that removes the extension from the database.
+
+- /usr/share/plc_api/extensions/<name>/migrations/[0-9][0-9][0-9]-{up,down}-*
+Migration scripts for the extension. One of the scripts for each version
+has to execute
+UPDATE plc_db_extensions SET version = <version> WHERE name = '<name>'